Elevator-door lock.



D. STEWART.

ELEVATOR DOOR LOCK. APPLiCATION FILED DEC. 2a, 1912.

Cit

DOUGLAS STEWART, OF MAYWOOD, ILLINOIS, ASSIGNOR OF ONE-HALF T RICHARD J. ROSS, OF CHICAGO, ILLINOIS.

ELEVATOR-DOOR LOCK.

" doors for freight elevators; to provide impro ed means adapted to automatically shift said mechanism into engaging position as the elevator arrives at the floor; to provide means normally urging said mechanism into its retracted position whereby the door is automatically released when the elevator moves away from the floor; and to provide improved mechanism of this kind which is simple and inexpensive in construction and 1 positive in operation.

An illustrative embodiment of this invention is shown in the accompanying drawings in which Figure 1 is an interior elevation, partly sectional, of an elevator door, the elevator platform being shown on a line with the floor and the doors closed. Fig. 2 is a transverse sectional elevation of the same taken on the line AA of Fig. 1. Fig. 3 is an 1 enlarged fragmentary detail in plan of the locking mechanism. Fig. at is an enlarged side elevation of the mechanism.

The mechanism herein shown and described is particularly adapted for use in buildings having freight elevators where passageways from floors into the elevator shaft are normally closed by means of doors during such times as the elevator is not at one of the floors.

In the construction shown, the door comprises upper and lower sections 1 and 2 slidably mounted in the guideways 3 and ar- -anged so that the section 1 may be moved upwardly and the section 2 downwardly when the elevator platform i l is at the floor 5, and it is desired to open the passage-way from the elevator to the floor. In order that the two sections of the door will move simultaneously, cables 6 are connected to the upper section 1 near the lower corners thereof Specification of Letters Patent. Patented S6191]. 25, 1916. Application filed. December 28, 1912. I

Serial No. 739,084.

and run over the pulleys 7 and connect to rods 8 which in turn are secured adjacent to the upper ends of the lower section 2.

The locking mechanism which secures the door sections in their open positions is mounted on a housing or casing A and comprises a detent or latch member 9 and a lever 13. The latch member 9 is preferably made of resilient material and is pivotally mounted its end between the walls of the housing A on a horizontal axis disposed=at right angles to the plane of the door. The upper end of the arm is ofi-set to provide a shoulder 11 and an inclined ledge 12. The lever 13 is constructed to provide lever arms and 16 extending in respectively opposite directions from the pivot 14 and offset axially at said pivot. he lever is mounted on the'housing A so that the arm 15 operates in a plane outside of the housing, and the arm 16 operates between the walls of the housing so as to engage and shift the latch member 9. The arm 15 carries an anti-friction roller 20 and the lever is normally urged to shift'the roller 20 into the path of the cam or shoe 22 carried on the elevator l, whereby the arm 16 is caused to shift the latch member 9' inwardly, toward the left of Fig. 1, and hold it in position for the shoulder 17 to be engaged by the shoulder 11. The movement of the latch member 9 inwardly is limited by a stop 18, and is normally urged toward its retracted position by means of a spring 19. The shoulder 17 is in the form of a rounded knob or lug formed on the arm 21 secured at one side of the door section 2 near the upper right hand corner thereof. "When the door sections are shifted out of their closed positions for opening communication through the passage-way from elevator to floor the shoulder 17 is engaged by the shoulder 11.

The mechanism is operated by means of a cam or shoe carried on the elevator. This cam is herein shown in the form of a plate or bar 22 mounted on a bracket 23 secured to the under side of the elevator platform 4 adjacent to one corner thereof. The plate '22 has the ends thereof inclined inwardly so as to provide an inclined approach for the roller 20.

A lever 24 is pivotally secured to the door section 2 and has a shoulder which is adapted to engage a lug 25 on the door section 1 for holding the doors in their closed positions.

The operation of the device shown is as follows: As the elevator approaches a floor the roller 20 is engaged by the cam or plate 22 and the corresponding latch member 13 is urged outwardly so that the part 16 en gages the latch member 9 and forces it inwardly against the stop 18. When the elevator is stop Bed with the platform a in a line withthe floor 5, he doors are unlocked and manually shifted by forcing the section 2 downwardly which causes the section 1 to elevate. As the top of the section 2 is forced below the lloor line the shoulder 17 engages the inclined portion of the latch member 9 and forces it back and passes under and into engagement with the shoulder 11. The door sections are thus held in their respective positions so long as the elevator remains at the floor. As the elevator moves away from the floor the cam recedes from the roller 20 of the arm 13 whereupon the spring 19 urges the latch member 9 outwardly so as to cause the disengagement of the shoulder 11 from the shoulder 1'7. The door sections being counterbalanced so as to normally close when not held open, immediately shift to their closed positions upon disengagement of said shoulders 11 and 17.

Although but one specific embodiment of this invention has been herein shown and describer it will be understood that numerous details of the construction shown may be altered or omitted without departing from the spirit of this invention as defined by the following claims,

I claim 1. The combination with an elevator, an elevator-shaft and a vertically slidable door, of locking mechanism for the door compris ing a rigid shoulder on the door, a cam on the elevator, a spring latch member pivotally mounted on a stationary part at one end of the door in position. to be shifted in the plane thereof to engage said shoulder and normally urged out of the path of said shoulder, and a lever pivoted on said stationary part of the side of said latch on an axis transverse to the plane of the door and having two arms extending in respectively opposite directions from the pivot and offset from each other axially at the pivot so as to move in different planes, one of said arms engaging said spring latch member adja' cent to its pivot and adapted to shift and hold said latch member in the path of said shoulder when the other said arm is engaged by said cam, said lever being normally urged to retract said one arm so as to release said latch member when said other arm is di engaged from said cam.

The combination with an elevator, an elevator-shaft and a vertically slidable door, of locking mechanism for the door comprising a housing adapted to be attached to a stationary part, a shoulder on the door, a spring latch member pivotally mounted at one end between the walls of said housing in position to be shifted to engage said shoulder and normally urged out of the path thereof, and a lever pivoted on said'housing and having two arms extending in respectively opposite directions from the pivot and oft-set from each other axially at the pivot, so as to have one of said arms located between the walls of said housing and the other outside thereof, said one arm engaging said spring latch member so as to shift and hold it in the path of said shoulder when the other said arm is engaged by said cam, said lever being normally ur 'ed to re-, lease said spring latch member when said arm is disengaged from said cam.

Signed at Chicago this 23rd day of December, 1912.

DOUGLAS STEWART. Witnesses:

Rrorreno J. Ross, EDWIN PHELPS.

Copies of this patent may be obtained for five cents each, by addressing the Gommissioner of Patents. Washington, D. C. 

